1 /* $OpenBSD: auth.h,v 1.76 2013/07/19 07:37:48 markus Exp $ */ 2 3 /* 4 * Copyright (c) 2000 Markus Friedl. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 */ 27 28 #ifndef AUTH_H 29 #define AUTH_H 30 31 #include <signal.h> 32 33 #include <openssl/rsa.h> 34 35 #ifdef HAVE_LOGIN_CAP 36 #include <login_cap.h> 37 #endif 38 #ifdef BSD_AUTH 39 #include <bsd_auth.h> 40 #endif 41 #ifdef KRB5 42 #include <krb5.h> 43 #endif 44 45 typedef struct Authctxt Authctxt; 46 typedef struct Authmethod Authmethod; 47 typedef struct KbdintDevice KbdintDevice; 48 49 struct Authctxt { 50 sig_atomic_t success; 51 int authenticated; /* authenticated and alarms cancelled */ 52 int postponed; /* authentication needs another step */ 53 int valid; /* user exists and is allowed to login */ 54 int attempt; 55 int failures; 56 int server_caused_failure; 57 int force_pwchange; 58 char *user; /* username sent by the client */ 59 char *service; 60 struct passwd *pw; /* set if 'valid' */ 61 char *style; 62 void *kbdintctxt; 63 char *info; /* Extra info for next auth_log */ 64 void *jpake_ctx; 65 #ifdef BSD_AUTH 66 auth_session_t *as; 67 #endif 68 char **auth_methods; /* modified from server config */ 69 u_int num_auth_methods; 70 #ifdef KRB5 71 krb5_context krb5_ctx; 72 krb5_ccache krb5_fwd_ccache; 73 krb5_principal krb5_user; 74 char *krb5_ticket_file; 75 char *krb5_ccname; 76 #endif 77 Buffer *loginmsg; 78 void *methoddata; 79 }; 80 /* 81 * Every authentication method has to handle authentication requests for 82 * non-existing users, or for users that are not allowed to login. In this 83 * case 'valid' is set to 0, but 'user' points to the username requested by 84 * the client. 85 */ 86 87 struct Authmethod { 88 char *name; 89 int (*userauth)(Authctxt *authctxt); 90 int *enabled; 91 }; 92 93 /* 94 * Keyboard interactive device: 95 * init_ctx returns: non NULL upon success 96 * query returns: 0 - success, otherwise failure 97 * respond returns: 0 - success, 1 - need further interaction, 98 * otherwise - failure 99 */ 100 struct KbdintDevice 101 { 102 const char *name; 103 void* (*init_ctx)(Authctxt*); 104 int (*query)(void *ctx, char **name, char **infotxt, 105 u_int *numprompts, char ***prompts, u_int **echo_on); 106 int (*respond)(void *ctx, u_int numresp, char **responses); 107 void (*free_ctx)(void *ctx); 108 }; 109 110 int auth_rhosts(struct passwd *, const char *); 111 int 112 auth_rhosts2(struct passwd *, const char *, const char *, const char *); 113 114 int auth_rhosts_rsa(Authctxt *, char *, Key *); 115 int auth_password(Authctxt *, const char *); 116 int auth_rsa(Authctxt *, BIGNUM *); 117 int auth_rsa_challenge_dialog(Key *); 118 BIGNUM *auth_rsa_generate_challenge(Key *); 119 int auth_rsa_verify_response(Key *, BIGNUM *, u_char[]); 120 int auth_rsa_key_allowed(struct passwd *, BIGNUM *, Key **); 121 122 int auth_rhosts_rsa_key_allowed(struct passwd *, char *, char *, Key *); 123 int hostbased_key_allowed(struct passwd *, const char *, char *, Key *); 124 int user_key_allowed(struct passwd *, Key *); 125 void pubkey_auth_info(Authctxt *, const Key *, const char *, ...) 126 __attribute__((__format__ (printf, 3, 4))); 127 128 struct stat; 129 int auth_secure_path(const char *, struct stat *, const char *, uid_t, 130 char *, size_t); 131 132 #ifdef KRB5 133 int auth_krb5(Authctxt *authctxt, krb5_data *auth, char **client, krb5_data *); 134 int auth_krb5_tgt(Authctxt *authctxt, krb5_data *tgt); 135 int auth_krb5_password(Authctxt *authctxt, const char *password); 136 void krb5_cleanup_proc(Authctxt *authctxt); 137 #endif /* KRB5 */ 138 139 #if defined(USE_SHADOW) && defined(HAS_SHADOW_EXPIRE) 140 #include <shadow.h> 141 int auth_shadow_acctexpired(struct spwd *); 142 int auth_shadow_pwexpired(Authctxt *); 143 #endif 144 145 #include "auth-pam.h" 146 #include "audit.h" 147 void remove_kbdint_device(const char *); 148 149 void disable_forwarding(void); 150 151 void do_authentication(Authctxt *); 152 void do_authentication2(Authctxt *); 153 154 void auth_info(Authctxt *authctxt, const char *, ...) 155 __attribute__((__format__ (printf, 2, 3))) 156 __attribute__((__nonnull__ (2))); 157 void auth_log(Authctxt *, int, int, const char *, const char *); 158 void userauth_finish(Authctxt *, int, const char *, const char *); 159 int auth_root_allowed(const char *); 160 161 void userauth_send_banner(const char *); 162 163 char *auth2_read_banner(void); 164 int auth2_methods_valid(const char *, int); 165 int auth2_update_methods_lists(Authctxt *, const char *, const char *); 166 int auth2_setup_methods_lists(Authctxt *); 167 int auth2_method_allowed(Authctxt *, const char *, const char *); 168 169 void privsep_challenge_enable(void); 170 171 int auth2_challenge(Authctxt *, char *); 172 void auth2_challenge_stop(Authctxt *); 173 int bsdauth_query(void *, char **, char **, u_int *, char ***, u_int **); 174 int bsdauth_respond(void *, u_int, char **); 175 int skey_query(void *, char **, char **, u_int *, char ***, u_int **); 176 int skey_respond(void *, u_int, char **); 177 178 void auth2_jpake_get_pwdata(Authctxt *, BIGNUM **, char **, char **); 179 void auth2_jpake_stop(Authctxt *); 180 181 int allowed_user(struct passwd *); 182 struct passwd * getpwnamallow(const char *user); 183 184 char *get_challenge(Authctxt *); 185 int verify_response(Authctxt *, const char *); 186 void abandon_challenge_response(Authctxt *); 187 188 char *expand_authorized_keys(const char *, struct passwd *pw); 189 char *authorized_principals_file(struct passwd *); 190 191 FILE *auth_openkeyfile(const char *, struct passwd *, int); 192 FILE *auth_openprincipals(const char *, struct passwd *, int); 193 int auth_key_is_revoked(Key *); 194 195 HostStatus 196 check_key_in_hostfiles(struct passwd *, Key *, const char *, 197 const char *, const char *); 198 199 /* hostkey handling */ 200 Key *get_hostkey_by_index(int); 201 Key *get_hostkey_public_by_index(int); 202 Key *get_hostkey_public_by_type(int); 203 Key *get_hostkey_private_by_type(int); 204 int get_hostkey_index(Key *); 205 int ssh1_session_key(BIGNUM *); 206 void sshd_hostkey_sign(Key *, Key *, u_char **, u_int *, u_char *, u_int); 207 208 /* debug messages during authentication */ 209 void auth_debug_add(const char *fmt,...) __attribute__((format(printf, 1, 2))); 210 void auth_debug_send(void); 211 void auth_debug_reset(void); 212 213 struct passwd *fakepw(void); 214 215 int sys_auth_passwd(Authctxt *, const char *); 216 217 #define AUTH_FAIL_MSG "Too many authentication failures for %.100s" 218 219 #define SKEY_PROMPT "\nS/Key Password: " 220 221 #if defined(KRB5) && !defined(HEIMDAL) 222 #include <krb5.h> 223 krb5_error_code ssh_krb5_cc_gen(krb5_context, krb5_ccache *); 224 #endif 225 #endif 226